Ankle injuries
From Medical-Wiki
The ankle is one of the most commonly injured joints in all of athletics. Some studies have estimated it as comprising one half of all such injuries. The lateral ankle complex, the anterior talofibular, calcaneofibular, posterior talofibular ligaments, is the site most commonly injured. [1]
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Anatomy of the ankle
The distal end of the tibia terminates in a large articular surface (the plafond), the prominent medial malleolus, and a less prominent posterior malleolus. The talar dome is wedge-shaped, wider anteriorly than posteriorly. The distal fibula forms the lateral malleolus. It is bound to the tibia by the anterior and posterior inferior tibiofibular ligaments, an inferior transverse ligament, and a syndesmosis ligament. The fibula is also attached to the talus and the calcaneus by another series of ligaments. The superficial and deep portions of the deltoid ligament attach the medial malleolus to the talus, calcaneus, and navicular.
Clinical presentation
When a patient presents with an ankle injury, it is important to determine the mechanism of injury. In addition, complaints of paresthesias or a cold foot raise the possibility of neurovascular compromise.
Diagnosis
Physical examination
Examination of an ankle may be difficult because of guarding. It is important to therefore glean as much information as possible from observation. Check for obvious deformity, ecchymosis, and degree of swelling. Begin to form an opinion as to what grade sprain the patient has: Grade I sprains—mild swelling; stretch to ligaments. Weight bearing possible. Grade II sprains—moderate swelling; incomplete tear of ligaments; mild instability but testing has an end point; pain with weight bearing. Grade III sprains—severe swelling; often pronounced ecchymosis; unstable; at least one ligament completely torn.
If films are not performed, then clinical evaluation of the ankle should be used in its assessment. Stability is checked through drawer and talar tilt examination techniques. However, guarding, spasm and swelling make these tests of limited value in an acute setting.
The anterior drawer test is done with the ankle at 90° to the leg. Grasp the heel and pull forward. At the same time, the other hand places posterior force on the tibia. A positive sign consists of dimpling at the anterolateral aspect of the ankle. This suggests compromise of the anterior talofibular ligament.
The talar tilt test is also performed with the ankle at 90° to the leg. Grab the heel, abduct, and invert it. An inability to reach a firm end point when compared to the contralateral side raises damage to the calcaneal fibular ligament.
The fibular compression test, or squeeze test, is done by placing the thumb on the tibia and the fingers at the mid point of the lower leg. Then, gently squeeze. Pain along the length of the fibula is a positive test and suggests fibular injury.
Talar dome fractures and transchondral fractures are often difficult to diagnose. Tarsal navicular fractures in particular may present as a diffuse, vague pain along the medial longitudinal arch or dorsum of the foot. This injury is often misdiagnosed as plantar fasciitis.
Radiological findings
Obviously, before cranking on an ankle, the possibility of fracture must be considered. Because of concern over cost and radiation exposure, there has been an effort to establish criteria for when x-rays are required. From this desire the Ottawa ankle rules were established. These are a set of criteria used to conservatively predict whether an ankle has been fractured. If they predict that an ankle has not been fractured, many emergency rooms will not do x-rays. Since their origination in 1996, these criteria have become time-tested.
Some ankle fractures may not be visible with an ankle series. A large ankle-joint effusion on the initial lateral radiograph suggests an occult fracture.
The exact nature of ligamentous injuries may be implied by plain radiographs, but MRI is a far more accurate means of assessment.
Utilization of Ottawa/Pittsburg knee rules
There are also Ottawa knee rules. Since their development, Pittsburg rules have been established and are preferred by some institutions—and not just in Pittsburg. [2]
If Ottawa rules suggest that x-rays should be performed, i.e. there is a reasob=nable chance the ankle has been fractured, a series of 3 conventional radiographs in anteroposterior, internal oblique (mortise), and lateral projection should be completed.
A relatively new term has crept into descriptions of ankle sprains—a “high” ankle sprain. This refers to an injury to the tibiofibular syndesmosis ligaments binding the distal ends of the tibia and fibula. [3]
Treatments
If a patient has a malleolar fracture, a dislocation, neurovascular compromise, tendon rupture, a wound that penetrates the joint, talar dome fracture, mechanical "locking" of the joint, or disruption of the ankle syndesmosis, an orthopedic referral should be made. A consult is also judicious in cases where a patient’s pain is out of proportion to clinical findings.
Uncomplicated sprains typically do not require consults. When caring for these sprains, initial efforts should be geared towards the prevention of swelling and the maintenance range of motion. The elements of RICE (rest, ice, compression and elevation) should be applied. The ice should be applied for 20 minutes every 2 or 3 hours. Even when cryotherapy is being used, gentle range of motion exercises should be initiated.
In addition, swelling may be decreased by applying pressure with bandaging using an elastic bandage. Elevation of the injured foot should be above the level of the heart. Crutches should be used for partial weight bearing. Since an edematous ankle is stiffened in a plantar-flexed, slightly inverted position, a removable device such as a plastic orthosis or a plaster splint may be used to oppose these forces. Circumferential casting is not typically used because it limits range of motion.
Perhaps one of the most common mistakes is immobilization for too long a period of time. As an ankle is stressed, the strength of replacement collagen is increased. Further, range of motion must be maintained.
Because strength, range of motion, and proprioceptive exercises are not simply intuitive, physical therapy referrals are appropriate. [4]
